An exhaust gas treatment device is mounted on a hydraulic excavator. As the exhaust gas treatment device, for example, a diesel particulate filter device (DPF), a diesel oxidation catalyst device (DOC), a selective catalytic reduction device (SCR), and the like are available.
Japanese Patent Laying-Open No. 2011-157721 (PTD 1) discloses such a structure that a DPF and an SCR are arranged at a certain distance from an inner wall surface of a rear peripheral wall forming an engine compartment.